Transparent tablet for evaluation of motor responses

Abstract

Transparent tablet for evaluation of motor responses furnishes the coordinates of the contact points of at least one conductive probe tip on tablet. The tablet is overlaid on its outer face by a resistive transparent film, such as tin dioxide. By the provision of a current-generating device in first and in second directions, voltage gradients are set up along the resistive transparent film in the first and second directions. The voltages picked up by the conductive probe tip at the point of contact are proportional to the distance of the point to the edges of the tablet along each of the directions. The numerical values of the point coordinates are furnished by the conversion to digital form, by an A/D converter, of the voltage.

1. TRANSPARENT TABLET FOR EVALUATION OF MOTOR RESPONSES furnishing coordinates of contact points of at least one conductive probe tip on a plate, wherein said plate is transparent and overlaid on an outer face by a continuous resistive transparent film, and means for setting up electric currents in first and second directions along said film, distinction between said currents being provided by identifying features specific to each of said currents. 
   
   
     2. TRANSPARENT TABLET FOR EVALUATION OF MOTOR RESPONSES as claimed in  claim 1 , wherein said identifying features consist of the timing of said currents provided by the alternate switching-on of the currents in said first and second directions. 
   
   
     3. TRANSPARENT TABLET FOR EVALUATION OF MOTOR RESPONSES as claimed in  claim 2 , wherein the coordinates of said contact points are determinated by a measurement of magnitudes of voltages picked up by said probe tip when touching said resistive transparent film, in each of the two said directions. 
   
   
     4. TRANSPARENT TABLET FOR EVALUATION OF MOTOR RESPONSES as claimed in  claim 2 , wherein the values of the DC voltages are digitized by an A/D converter. 
   
   
     5. TRANSPARENT TABLET FOR EVALUATION OF MOTOR RESPONSES as claimed in  claim 2 , wherein said currents in the first and second directions are provided by applying a DC voltage between the left-hand and the right-hand vertical edges of said tablet in a first half-cycle, and of a DC voltage between the upper and lower edges of the tablet in a second half-cycle, operation of an A/D converter being synchronized with said first and second half-cycles. 
   
   
     6. TRANSPARENT TABLET FOR EVALUATION OF MOTOR RESPONSES as claimed in  claim 2 , wherein the transparent resistive film consists of tin dioxide. 
   
   
     7. TRANSPARENT TABLET FOR EVALUATION OF MOTOR RESPONSES as claimed in  claim 3 , wherein the transparent resistive film consists of tin dioxide. 
   
   
     8. TRANSPARENT TABLET FOR EVALUATION OF MOTOR RESPONSES as claimed in  claim 1 , wherein said identifying features consist of two different frequencies, each frequency being associated with the current in one of said two directions, and alternating voltages picked up by the probe tip are forwarded to bandpass filters tuned to a first and a second said frequencies, followed by rectification and filtering of resulting DC voltages. 
   
   
     9. TRANSPARENT TABLET FOR EVALUATION OF MOTOR RESPONSES as claimed in  claim 8 , wherein the values of the DC voltages are digitized by an A/D converter. 
   
   
     10. TRANSPARENT TABLET FOR EVALUATION OF MOTOR RESPONSES as claimed in  claim 8 , wherein the transparent resistive film consists of tin dioxide. 
   
   
     11. TRANSPARENT TABLET FOR EVALUATION OF MOTOR RESPONSES as claimed in  claim 9 , wherein the transparent resistive film consists of tin dioxide. 
   
   
     12. TRANSPARENT TABLET FOR EVALUATION OF MOTOR RESPONSES as claimed in  claim 1 , wherein said plate has a rectangular shape, current lines being parallel to X and Y axes, respectively. 
   
   
     13. TRANSPARENT TABLET FOR EVALUATION OF MOTOR RESPONSES as claimed in  claim 12 , wherein the transparent resistive film consists of tin dioxide. 
   
   
     14. TRANSPARENT TABLET FOR EVALUATION OF MOTOR RESPONSES furnishing coordinates of contact points of at least one conductive probe tip on a plate, wherein said plate is transparent and overlaid on its outer face by a resistive transparent film, and means for setting up electric currents in first and second directions along said film, distinction between said currents being provided by identifying features specific to each of said currents,
 wherein said plate has a rectangular shape, current lines being parallel to X and Y axes, respectively,  
 wherein said currents in the first and second directions are provided by applying a DC voltage between the left-hand and the right-hand vertical edges of said tablet in a first half-cycle, and of a DC voltage between the upper and lower edges of the tablet in a second half-cycle, the operation of an A/D converter being synchronized with said first and second half-cycles.  
 
   
   
     15. TRANSPARENT TABLET FOR EVALUATION OF MOTOR RESPONSES as claimed in  claim 14 , wherein the transparent resistive film consists of tin dioxide. 
   
   
     16. TRANSPARENT TABLET FOR EVALUATION OF MOTOR RESPONSES furnishing coordinates of contact points of at least one conductive probe tip on a plate, wherein said plate is transparent and overlaid on its outer face by a resistive transparent film, and means for setting up electric currents in first and second directions along said film, distinction between said currents being provided by identifying features specific to each of said currents,
 wherein two probes are provided, voltages picked up by said two probes being alternately monitored.  
 
   
   
     17. TRANSPARENT TABLET FOR EVALUATION OF MOTOR RESPONSES as claimed in  claim 16 , wherein the transparent resistive film consists of tin dioxide. 
   
   
     18. TRANSPARENT TABLET FOR EVALUATION OF MOTOR RESPONSES furnishing coordinates of contact points of at least one conductive probe tip on a plate, wherein said plate is transparent and overlaid on its outer face by a resistive transparent film, and means for setting up electric currents in first and second directions along said film, distinction between said currents being provided by identifying features specific to each of said currents,
 wherein said identifying features consist of the timing of said currents provided by the alternate switching-on of the currents in said first and second directions,  
 wherein said currents in the first and second directions are provided by applying a DC voltage between left-hand and right-hand vertical edges of said tablet in a first half-cycle, and applying a DC voltage between upper and lower edges of the tablet in a second half-cycle, operation of an A/D converter being synchronized with said first and second half-cycles.